Make [jest-cli] not error when no tests are found with --findRelatedTests, --lastCommit or --onlyChanged options (#5127)

Author: emilgoldsmith

CHANGELOG.md

@@ -1,4 +1,11 @@
 ## master
+
+### Features
+
+* `[jest-cli]` Make Jest exit without an error when no tests are found in
+  the case of `--lastCommit`, `--findRelatedTests`, or `--onlyChanged` options
+  having been passed to the CLI
+
 ## jest 22.0.6
 
 ### Fixes

integration_tests/__tests__/no_tests_found.test.js

@@ -0,0 +1,69 @@
+/**
+ * Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow
+ */
+
+'use strict';
+
+const path = require('path');
+const runJest = require('../runJest');
+
+const DIR = path.resolve(__dirname, '../no_tests_found-test');
+
+describe('No tests are found', () => {
+  test('fails the test suite in standard situation', () => {
+    const result = runJest(DIR, ['--testPathPattern', '/non/existing/path/']);
+    const status = result.status;
+    const stdout = result.stdout.toString();
+
+    expect(stdout).toMatch('No tests found');
+    expect(status).toBe(1);
+  });
+
+  test("doesn't fail the test suite if --passWithNoTests passed", () => {
+    const result = runJest(DIR, [
+      '--testPathPattern',
+      '/non/existing/path/',
+      '--passWithNoTests',
+    ]);
+    const status = result.status;
+    const stdout = result.stdout.toString();
+
+    expect(stdout).toMatch('No tests found');
+    expect(status).toBe(0);
+  });
+
+  test("doesn't fail the test suite if using --lastCommit", () => {
+    // Since there are no files in DIR no tests will be found
+    const result = runJest(DIR, ['--lastCommit']);
+    const status = result.status;
+    const stdout = result.stdout.toString();
+
+    expect(stdout).toMatch('No tests found');
+    expect(status).toBe(0);
+  });
+
+  test("doesn't fail the test suite if using --onlyChanged", () => {
+    // Since there are no files in DIR no tests will be found
+    const result = runJest(DIR, ['--onlyChanged']);
+    const status = result.status;
+    const stdout = result.stdout.toString();
+
+    expect(stdout).toMatch('No tests found');
+    expect(status).toBe(0);
+  });
+
+  test("doesn't fail the test suite if using --findRelatedTests", () => {
+    // Since there are no files in DIR no tests will be found
+    const result = runJest(DIR, ['--findRelatedTests', '/non/existing/path']);
+    const status = result.status;
+    const stdout = result.stdout.toString();
+
+    expect(stdout).toMatch('No tests found');
+    expect(status).toBe(0);
+  });
+});

integration_tests/__tests__/pass_with_no_tests.test.js

@@ -153,7 +153,12 @@ export default (async function runJest({
       globalConfig,
     );
 
-    if (globalConfig.passWithNoTests) {
+    if (
+      globalConfig.passWithNoTests ||
+      globalConfig.findRelatedTests ||
+      globalConfig.lastCommit ||
+      globalConfig.onlyChanged
+    ) {
       new Console(outputStream, outputStream).log(noTestsFoundMessage);
     } else {
       new Console(outputStream, outputStream).error(noTestsFoundMessage);